Thermoplastic fiber concentrate methods and articles

ABSTRACT

A feedstock concentrate material, including a first phase including fibers having a length greater than 5 mm; and a polymeric phase including a first polyolefin having a first melt flow rate; and a second polyolefin having a second melt flow rate. Kits, methods of using and resulting articles including the concentrate are also disclosed.

CLAIM OF BENEFIT OF FILING DATE

The present application claims the benefit of the filing date of U.S.Application Ser. No. 60/890,002, filed Feb. 15, 2007, and PCTApplication No. PCT/US07/74398 filed Jul. 26, 2007 (from which thisapplication is a continuation), hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates generally to improved fiber reinforcedthermoplastic articles, and specifically to thermoplastic articlesprepared from a fiber concentrate.

BACKGROUND OF THE INVENTION

The use of filled or reinforced thermoplastics continues to attractattention for use in various applications. One technical issue faced inthe art (e.g., for use in automotive or other applications) is the needto provide substantially uniform dispersions. The art has beeninvestigating alternative approaches to the manufacture of highintegrity plastics, particularly those in which a glass fiber phase isincluded.

Examples of efforts to improve fiber dispersions include, withoutlimitation, Webster, U.S. Pat. No. 6,756,429 B2, “Method for ImprovingFiber Dispersion and Orientation in Let-Downs of Long Fiber ReinforcedComposites,” (assigned to Clariant), hereby incorporated by reference.That patent illustrates polyamide matrices incorporating modifiers.

European Patent Application No. EP1 364760A1, “Emission-Reduced Articlesfrom Long Fiber Reinforced Polypropylene,” (assigned to Borealis),hereby incorporated by reference, teaches granules containing glassfibers coated first with one molten polypropylene, and then subsequentlycoated by a second polypropylene.

Published U.S. Pat. No. 7,045,202, “Long Glass Fiber Filler ReinforcedResin Material for Molding, Method for Molding Molded Article, andMolded Article Molded by the Method,” (Mazda Motor Corp.), herebyincorporated by reference, addresses a masterbatch having apolypropylene matrix and including grafted polypropylene and glassfibers. See also, Published US Patent Application US20020052440A1, “LongGlass Fiber Filler Reinforced Resin material for Molding,Injection-Molded Article Molded by Injection-Molding the Resin Material,and Method for Molding the Resin Material,” (Mazda Motor Corp.) herebyincorporated by reference.

European Patent Application No. EP 0663418 AI, “Mixture of Long GlassFiber-Reinforced Polypropylene and Polypropylene resin and MoldingsFormed Therefrom,” (Kawasaki Steel Corp.), hereby incorporated byreference, addresses a mixture that includes glass fibers coupled withgrafted polypropylene.

Nothwithstanding efforts to date, there remains a need for improvedsystems for making fiber reinforced thermoplastic articles, andparticularly articles that exhibit good dispersion characteristics, suchas for avoiding the formation of fiber clusters, and, particularly fiberclusters that impair other manufacturing process steps (e.g., laserscoring).

There also remains a need for improved fiber-containing feedstockmaterials that remain substantially in tact during dry handling andprocessing steps in advance of melting steps.

SUMMARY OF THE INVENTION

The present invention meets one or more of the above needs by providingan improved fibrous concentrate, and particularly a long glass fiber(e.g., an average length greater than 5 mm, and more specificallygreater than 10 mm) concentrate, wherein the fibrous phase is present ina polymeric matrix in an amount of at least about 20 percent by weight,and more preferably greater than 50 percent by weight (e.g., about 50 toabout 75 percent by weight, such as about 60 percent by weight). Theinvention is predicated upon the recognition that unique properties areattainable by the manufacture and use of a feedstock concentratematerial that includes a first reinforcement phase (e.g., an organicand/or inorganic reinforcement phase, such as one including fibershaving an average length greater than 5 or even 10 mm, which phase maybe generally axially aligned, randomly oriented or a combinationthereof); and a polymeric phase including a first polymer (e.g., apolyolefin such as polypropylene) present in an amount of 50 percent byweight or greater of the polymeric phase and having a first melt flowrate, and a second polymer (e.g., a polyolefin such as polypropylene)present in an amount of less than 50 percent by weight of the polymericphase, and having a second melt flow rate that is greater than the firstmelt flow rate.

The present invention also contemplates methods for making theconcentrates, articles made from the concentrates, kits that include theconcentrate and methods for making the articles.

The concentrates herein offer one or more desirable characteristics,such as attractive and efficient fiber wetting characteristics, fiberdispersion characteristics, or mechanical properties. It is alsopossible that the concentrates exhibit a relatively low fiber breakagerate during manufacture and/or handling of the concentrate. Articlesmade with the concentrate are believed to exhibit a relatively lowincidence of fiber clustering, if any at all, thereby also yielding areduced likelihood of material scrap as a result of scoring (e.g., laserscoring) or other processing steps. Other benefits are also potentiallyachievable, such as the ability to reduce the amount of peroxide-crackedpolypropylene as a feedstock material for polypropylene based plastics,and hence a potential for reduced emissions or other undesired gasses orvapors.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is an x-ray micrograph illustrating an expected microstructure ofa relatively long glass fiber reinforced plastic outside of theteachings herein.

FIG. 2 is an x-ray micrograph illustrating an expected microstructure ofa relatively long glass fiber reinforced plastic according to theteachings herein.

DETAILED DESCRIPTION

Unless otherwise specified, percentages herein are expressed in percentby weight; and melt flow rates herein are at 230° C./2.16 kg, per ISO1133, and are expressed as g/10 minutes.

In general, the present invention is directed to reinforced plastics,and specifically fiber reinforced thermoplastics. The present inventioncontemplates an improved fibrous concentrate useful to prepare suchreinforced plastics, and particularly a relatively long glass fiberconcentrate, wherein the fibrous phase is present in an amount of atleast about 20 percent by weight, and more preferably greater than 50percent by weight (e.g., about 50 to about 75 percent by weight, such asabout 60 percent by weight). Unique properties are attainable by themanufacture and use of a feedstock concentrate material that includes afirst reinforcement phase (e.g., an organic and/or inorganicreinforcement phase, such as one including fibers having an averagelength greater than 5 mm, and more specifically greater than 10 mm,which phase may be generally axially aligned, randomly oriented or acombination thereof; and a polymeric phase including a first polyolefinpresent in an amount of 50 percent by weight or greater (e.g., at leastabout 65 percent by weight, such as about 75 to about 90 percent byweight) of the polymers in the polymeric phase and having a first meltflow rate, and a second polyolefin present in an amount of less than 50percent by weight (e.g., below about 35 percent by weight, such as about10 to about 25 percent by weight) of the polymers in the polymericphase, and having a second melt flow rate that is greater than the firstmelt flow rate.

In a particular illustration of the invention, the fibers may beorganic, inorganic, or both, and specifically the fibers are relativelylong (e.g., an average length greater than about 5 mm or morespecifically greater than about 10 mm). A preferred fiber is a glassfiber, which may be coated, or uncoated over substantially all of, or atleast a portion of the length of the fiber. The invention is not limitedto relatively long glass fibers, and fibers of other lengths, materials,or both may be included, as may be particulates. For example, the fibersmay include one or more of a ceramic, carbon, graphite, polymer (e.g.,aramid), metal, natural fiber (e.g., hemp, jute, sisal, or the like) orany combination thereof. Thus the fibers may be generally organic,generally inorganic, or a combination of both.

Examples of average fiber lengths in the feedstock concentrate materialrange from above about 5 mm, and more specifically above about 10 mm,e.g., from about 5 to about 50 mm, or more specifically greater than 10mm to about 30 mm in length (e.g., about 11 mm to about 25 mm).Preferably, at least about 50 percent by weight of the fibers will belonger than 10 mm, and more preferably at least about 65 (or even about75) percent by weight of the fibers will be longer than about 10 mm.Fiber diameters typically will range from about 3 to about 100 microns,and more specifically about 5 to about 25 microns (e.g., about 17microns). It will be appreciated that in resulting final particles(e.g., post-injection molding), fiber lengths may be reduced relative tothe initial fiber length. Thus, the above lengths generally refer tofiber lengths as they would exist in the feedstock concentrate material.In final articles, the resulting average fiber length will typically beabout 20 to about 80% of the initial length and more specifically about40 to about 70% of the initial length. Thus, for example, when averagefiber lengths are about 11 mm in the feedstock concentrate material, inan injection molded article employing the feedstock concentratematerial, the average fiber length will be about 2 to about 9 mm, andmore preferably about 5 to 8 mm, and still more preferably about 6 to 7mm.

One approach is to employ fibers that are pre-treated or otherwisemodified to improve one or more of their characteristics. For example,one approach is to coat the fibers with a chemical agent (e.g., acoupling agent, a surface property modifier, a stabilizer or othersuitable agent). By way of one specific example, fibers may be treatedwith a sizing agent for physically and/or chemically improving thetenacity of the subsequent interfacial bond with a polymeric matrix, forprotecting the surface of the fibers from damage or both. The sizingwill typically include a suitable film forming agent, a coupling agent(e.g., a silane such as an alkoxysilane), and optionally a lubricant orother agent. It may be possible to include for at least part of thesizing a polypropylene-based coupling agent (e.g., including a maleicanhydride grafted polypropylene coupling agent).

Fibers may be provided as individual fibers, e.g., chopped and/orcontinuous fibers, that are randomly oriented relative to each other,axially aligned relative to each other, woven or any combinationthereof, and which may thereafter be dispersed into the polymericmatrix. It is also contemplated that the fibers will be provided in abundle, by which the fibers are generally axially aligned. One specificapproach herein contemplates providing a continuous length of a fiberbundle that is impregnated with the polymeric phase and thereafter cut.In this manner, resulting impregnated materials (e.g., the feedstockconcentrate material herein) may have fibers generally sharing a commonaxial orientation. The invention is not so limited, however, and it ispossible that the feedstock concentrate material could include randomlyoriented fibers, one or more ordered or aligned orientation portions, afiber weave, a fiber winding, or any combination thereof.

One example of a suitable fiber is an E-glass fiber roving bundle, e.g.,having a generally continuous length, such as that availablecommercially from PPG FiberGlass Europe under the designation TUFROV®4599 fiber glass. Glass types other than or in addition to E-glass maybe employed, such as S-glass, T-glass, AR-glass, C-glass, R-glass orotherwise.

In general, the invention herein contemplates the manufacture of ashaped article, pursuant to which at least one feedstock, and morespecifically at least two feedstock materials (e.g., the feedstockconcentrate material herein and a diluent polymer) are combined, such aswhile in a softened or a molten state, and then introduced into a cavityof a tool for forming a shaped article within the tool cavity.Desirably, the reinforcement phase is introduced into the tool cavity aspart of at least one of the feedstock materials. For example, it isintroduced as a feedstock concentrate material. Typically the feedstockconcentrate will have a relatively high concentration of thereinforcement phase, which will then be diluted in the final article bythe presence of at least one diluent polymeric material, such as forforming a resulting material that includes a reinforcement phaseconcentration of from about 5 to about 50 percent by weight, and morespecifically about 20 percent by weight to about 40 percent by weight(e.g., about 20 percent by weight, about 30 percent by weight, or evenabout 40 percent by weight). The latter diluent polymeric material isintroduced along with the feedstock material, such as by mixing thediluent polymeric material feedstock with the feedstock concentratematerial, preferably before or during a step of introducing thematerials into the tool cavity. Without limitation, the feedstockconcentrate material may be dry blended with the diluent polymericmaterial feedstock and the resulting mixture heated for softening ormelting the polymeric phases; the feedstock concentrate material may beblended with the diluent polymeric material feedstock and simultaneouslyheated for softening or melting the polymeric phases, or a combinationthereof. The softened or molten material is introduced into a toolcavity for shaping it and it is solidified or otherwise hardened.

The feedstock concentrate material herein may be any suitable size orshape. In general, it may be elongated (e.g., as a rod), granular,substantially symmetrical in shape about at least one axis,substantially asymmetrical in shape about at least one axis,substantially solid, porous, or any combination thereof. Individualparticles of the feedstock concentrate material may have their largestdimension (e.g., length, diameter, height, width or thickness), about 5mm or larger, more specifically about 8 mm or larger, and still morespecifically about 10 mm or longer. For example, it is contemplated thatthe largest dimension will equal or exceed the average length ofreinforcement phase fibers in the feedstock concentrate material.Smaller sizes are also possible as well.

In addition to the reinforcement phase, within the feedstock concentratematerial (or possibly external of the feedstock concentrate material,but combined therewith prior to blending with any diluent polymericmaterial) there will be at least one first polymeric material,particularly a thermoplastic polymeric material, and preferably acombination of at least a first and a second thermoplastic polymericmaterials. Though the invention herein is described with specificreference to certain polyolefinic polymers, it is not so limited. Forexample, though embodiments herein teach the use of a polymeric material(homopolymer, co-polymer, blend or other combination) includingpolypropylene, other polymers may be employed, such as polyethylenes,polyamides, polycarbonates, polystyrenes, polyesters, or any combinationthereof.

A particular preferred approach is to employ an amount of the firstpolymeric material that is more than the amount of the second polymericmaterial. For example, it is possible to use as the first polymericmaterial of the polymeric phase in the feedstock concentrate material amajor amount of a first polymer (e.g., a polyolefin such aspolypropylene) having a first melt flow rate, and to also employtherewith in the feedstock concentrate material a minor amount of asecond polymer (e.g., a polyolefin such as polypropylene) having asecond melt flow rate that is higher than the first melt flow rate. Forexample, the polymeric phase of the feedstock concentrate materialincluding a first polymer (e.g., a polyolefin) present in an amount ofat least about 25 percent by weight, and more particularly about 50percent by weight or greater (e.g., at least about 65 percent by weight,such as about 75 to about 90 percent by weight) of the polymeric phaseand having a first melt flow rate, and a second polymer (e.g., apolyolefin) present in an amount of less than 50 percent by weight(e.g., below about 35 percent by weight, such as about 10 to about 25percent by weight) of the polymeric phase, and having a second melt flowrate that is greater than the first melt flow rate by a factor of atleast about 1.5, by a factor of at least about 2.5, or even by a factorof at least 4 (e.g., the second melt flow rate of the second polymer isgreater than the first melt flow rate of the first polymer by a factorof about 1.5 to about 5.5, and more specifically about 2 to about 4.5).Thus, within the polymeric phase there will be a higher concentration ofthe lower melt flow rate material.

The relative amounts of the polymeric material and other ingredients inthe feedstock concentrate material relative to the reinforcement phasemay vary as desired. One preferred approach is to employ greater thanabout 20 percent by weight reinforcement phase (e.g., glass fiber) ofthe feedstock concentrate material, and more specifically about 50 toabout 70 percent by weight reinforcement phase (e.g., glass fiber) ofthe feedstock concentrate material, and still more specifically about 60percent by weight reinforcement phase (e.g., glass fiber) of thefeedstock concentrate material, with the remainder to include or evenconsist essentially of the polymeric phase.

By way of illustration, it is desirable that the first polymericmaterial (e.g., a polyolefin such as polypropylene) has a melt flow rateat 230° C./2.16 kg, per ISO 1133 of less than about 150 g/10 minutes,more specifically less than about 100 g/10 minutes, and still morespecifically below about 80 g/10 minutes, and event still morespecifically below about 60 g/10 minutes. Further, it is desirable thatthe second polymeric material (e.g., a polyolefin such as polypropylene)has a melt flow rate at 230° C./2.16 kg, per ISO 1133 of at least about220 g/10 minutes, more specifically at least about 250 g/10 minutes, andstill more specifically at least about 300 g/10 minutes.

One example, without limitation, of a suitable first polymeric materialof the polymeric phase of the feedstock concentrate material has a meltflow rate in the range of about 40 to about 65 g/10 minutes (e.g., about52 g/10 minutes), and at least one (and preferably a combination of all)property selected from a flexural modulus per ISO 178 of at least about1200 MPa (e.g., about 1650 MPa), a tensile strength at yield per ISO527-2 of at least about 25 MPa (e.g., about 37 MPa), a tensileelongation at yield per ISO 527-2 of at least about 5 percent (e.g.,about 9 percent), or a Charpy (notched) impact strength (23° C.) per ISO179-1/1 eA or at least about 1.5 KJ/m² (e.g., about 2.5 KJ/m²).Desirably the first polymeric material will be a polypropylenehomopolymer, although copolymers (e.g., random and/or block copolymers)that include propylene may be employed also. An example of a suitablecommercially available material for use as the first polymeric materialof the feedstock concentrate material is H734-52RNA Polypropylene Resinfrom The Dow Chemical Company.

One example, without limitation, of a suitable second polymeric materialof the polymeric phase of the feedstock concentrate material has a meltflow rate in the range of about 300 to about 600 g/10 minutes (e.g.,about 450 g/10 minutes). Desirably the second polymeric material will bea polypropylene homopolymer, although copolymers (e.g., random and/orblock copolymers) that include propylene may be employed also. Anexample of a suitable commercially available material for use as thesecond polymeric material of the feedstock concentrate material isBorflow HL504FB from Borealis.

Within the typical feedstock concentrate material herein, it iscontemplated that the relative amounts of the first polymeric materialto the second polymeric material (e.g., a first polypropylene having afirst melt flow rate and a second polypropylene having a second meltflow rate), will be about 1.1 to about 12 parts of the first polymericmaterial to about 1 part of the second polymeric material, morespecifically about 3 to about 9 parts of the first polymeric material toabout 1 part of the second polymeric material, and still morespecifically about 5 to about 6 parts of the first polymeric material toabout 1 part of the second polymeric material.

It also may be desirable to include in the feedstock concentratematerial one or more other ingredients, such as an ingredient selectedfrom one or more of an anti-oxidant, a stabilizer, a colorant, a moldrelease agent, an anti-static agent, a nucleating agent or anycombination thereof. One way to incorporate some or all of theseingredients is to provide the ingredients in a previously compoundedingredients concentrate, e.g., as particulates of the ingredientsdispersed in a polymeric matrix, including a carrier polymer. It ispossible that such a previously compounded ingredients concentrateparticulate will include one or more of an anti-oxidant, a stabilizer, acolorant, a coupling agent, a flame retardant, a mold release agent, ananti-static agent, a nucleating agent, filler, processing aid, or anycombination thereof (e.g., a combination including a colorant, ananti-oxidant, and a stabilizer), such ingredients being dispersed(randomly, substantially uniformly or otherwise) in a polymeric matrixthat includes a carrier polymer that is substantially the same as or isdifferent from one of the first polymer, the second polymer, or anotherpolymer present in the feedstock concentrate material. By way ofspecific example, in one embodiment, it is contemplated that one or moreof an anti-oxidant (e.g., IRGANOX® 1010 antioxidant from Ciba, IRGANOX®PS802 antioxidant), or a combination thereof, a stabilizer (e.g., anactive phosphite, such as a compound includingtris-(2,4-di-tert-butylphenyl) phosphite such as IRGAFOS® 168 stabilizerfrom Ciba), a colorant (e.g., carbon black, pigment or combinationthereof), or any combination thereof, is compounded with a polyolefinicpolymer (e.g., polypropylene) such as the second polymeric materialdescribed previously, such as one having a melt flow rate of about 300to about 600 g/10 minutes (e.g., about 450 g/10 minutes). Any stabilizermay be present in the ingredients concentrate in an amount of up toabout 30 percent by weight, or even as much as about 50 percent byweight of the ingredients concentrate, e.g., about 3 to about 15 percentby weight, and more specifically about 5 to about 10 percent by weight.Any antioxidant may be present in an amount up to about 30 percent byweight, or even as much as about 50 percent by weight of the ingredientsconcentrate, e.g., about 3 to about 15 percent by weight, and morespecifically about 5 to about 10 percent by weight of the ingredientsconcentrate. The colorant may be employed in any suitable amount. Forexample, if employed, it may range up to about 50 percent by weight fromabout 5 to about 25 percent by weight (e.g., about 15 percent by weightof the ingredients concentrate). The ingredients will preferably bedispersed in a polymeric carrier for the ingredients concentrate. Forexample, if employed, a polymer (e.g., a polypropylene, such as thefirst and/or second polymeric material of the feedstock materialconcentrate) likely will be present in an amount greater than about 35percent by weight or even greater than about 50 percent by weight (e.g.,about 60 to about 80 percent by weight) of the ingredients concentrate.Thus, it is contemplated that the first and/or second material of thefeedstock material concentrate will be introduced into the concentrate,in part or in whole, as a component of the ingredients concentrate.

The above ingredients are but examples of specific ingredients that maybe employed herein. Other additives, modifiers, stabilizers and/orfillers may also be employed, either as part of the ingredientsconcentrate, independent therefrom, or both.

The feedstock concentrate material may further include one or morecoupling agents, such as a grafted polypropylene coupling agent, andmore specifically, a maleic anyhydride grafted polypropylene couplingagent, such as that commercially available under the trade designationPOLYBOND® 3200 coupling agent from Chemtura, or OREVAC™ CA-100 resinfrom Arkema. The coupling agent may be added to the feedstockconcentrate material independent of the ingredients concentrate, or itmay be included within the ingredients concentrate. The coupling agent,if employed at all, will be employed in an amount of about 0.5 to about5 percent by weight of the feedstock concentrate material, and morespecifically about 1 to about 3 percent by weight of the feedstockconcentrate material.

An example of one ingredients concentrate may have the composition(expressed in approximate parts by weight of the ingredientsconcentrate) of Table 1.

TABLE 1 Preferred More Preferred Ingredient Concentration IngredientConcentration Carrier Polymer >35 BORFLOW ™ 70 HL504FB Colorant 0 to 50carbon black 15 Stabilizer 0 to 50 IRGAFPS ® 168 6.7 Anti-Oxidant 0 to50 IRGANOX ® 1010 3.3 IRGANOX ® 5.0 PS802

An example of a feedstock concentrate material might have thecomposition (expressed in approximate parts by weight of the feedstockconcentrate material) of Table 2.

TABLE 2 Preferred More Preferred Ingredient Concentration IngredientConcentration First Polymer at least 25 H734-52RNA 32.4 Second Polymer<25 BORFLOW ™ 4 HL504FB Ingredients 0.1 to 15 Table 1 Concentrate 2.1Concentrate Glass fiber at least 20 TUFROV ® 4599 60 Coupling agent upto 5 OREVAC ™ 1.5 CA-100

In general, the feedstock concentrate material herein may be made by aprocess that involves mixing the ingredients other than the fiberstogether to form one or more compounds and impregnating a plurality ofthe fibers with the compounds. Though many suitable processingtechniques may be employed, such as melt blending techniques (e.g.,melt-extruding), one approach is to impregnate a bundle of fibers, suchas by way of a pultrusion process. An example of one such process isdescribed, without limitation, in U.S. Pat. No. 5,834,056, “Process andApparatus for Fiber Bundle Impregnation” (Institut FuerVerbundwerkstoffe GmbH), hereby incorporated by reference. In general, agenerally continuous fiber bundle is supported and fed to one or moresites at which the polymeric phase of the concentrate (e.g., in a liquidextruded state) is contacted with the fibers. The polymeric phase willthereby impregnate the bundle. Resulting impregnated material can beground, cut or otherwise sections to form individual pellets, rods orother granules. As can be seen, it is possible that the impregnatedfibers will be aligned generally axially with each other, namely in thesame general direction.

In general, the feedstock concentrate material herein will be diluted inconnection with the manufacture of a shaped article. For example, it isexpected that a resulting article will have a fiber content (e.g., aglass fiber) of from about 5 percent by weight of the resulting materialto about 50 percent by weight of the resulting material, and morespecifically about 20 to about 40 percent by weight of the resultingmaterial (e.g., about 20 percent by weight fiber, about 30 percent byweight fiber, or about 40 percent by weight fiber). Accordingly theamount of any diluent polymer to be employed will be a function of thedesired end concentration. For example, without limitation, for anarticle with a resulting fiber concentration of about 30 percent byweight, about 50 parts by weight of a feedstock concentrate materialwith about 60 percent by weight fiber will be mixed with about 50 partsby weight of a diluent polymer.

The diluent polymeric material to be mixed (e.g., as a feedstockmaterial) with the feedstock concentrate material may be any suitablepolymeric material, and preferably will be a thermoplastic (e.g., apolyolefin, a polyamide, a polycarbonate, a polystyrene, a polyester, orany combination thereof). One particularly preferred material willinclude polypropylene, and specifically a reactor grade polypropylene.For example, it is desired to employ a polypropylene impact copolymer, apolypropylene homopolymer or a combination thereof, Preferably the meltflow rate of the diluent polymer will be less than about 150 g/10minutes, and more specifically less than about 100 g/10 minutes, andstill more preferably less than about 75 g/10 minutes (e.g., about 30 toabout 60 g/10 minutes). The diluent polymer preferably also will exhibitat least one or both of a flexural modulus per ISO 178 of at least about800, and more preferably at least about 950 MPa (e.g., about 1350 MPa),or a tensile strength at yield per ISO 527-2 of at least about 15 MPa(e.g., about 20 MPa). Without limitation, one specific example of apreferred polypropylene is a polypropylene impact copolymer availablecommercially from The Dow Chemical Company under the designationC705-44NAHP. Other examples of diluent polymeric materials include oneor any combination of homopolymers of propylene, or copolymers includingpropylene, such as propylene-ethylene random copolymers,propylene-ethylene block copolymers, propylene-EPDM copolymers, orpropylene-butene copolymers.

For making an article using the feedstock concentrate material herein,generally, the feedstock concentrate material will be combined with oneor more diluent polymeric materials. The step of combining the feedstockmaterials may take place using any suitable mixing technique, such asdry blending, melt blending, or a combination thereof. For example, oneapproach is to provide a source of feedstock concentrate material,provide a source of diluent polymeric material, and to deliver both thefeedstock concentrate material and the diluent polymeric material (andany other optional ingredients) to a mixing site (e.g., a mixinghopper), at which they are mixed together (such as by dry mixing).Before, during and/or after mixing, the respective feedstock materialsmay be dosed in their desired amounts, such as by a gravimetric dosingmachine, a volumetric dosing machine (e.g., employing a screw meter or arotating disc), or any combination thereof. Before, during, and/or aftermixing, the feedstock materials are heated, particularly to liquefy thepolymeric components of the materials. The liquid is shaped andsolidified within a cavity of a tool, such as within an injection moldcavity.

In general, suitable art-disclosed techniques may be employed formolding. For example, one or more of the feedstock materials may bedried in an air circulated oven for about 2 to 4 hours at about 80 toabout 90° C. The feed zone is maintained at about 190 to about 220° C.,with a barrel temperature of about 220 to about 280° C., and a moldtemperature of about 20 to about 60° C. The mold optionally may be watercooled. For example, one illustrative profile may realize a temperaturedifference of about 50° C. from nozzle to feeding area. Screw rotation,dosaging, back pressure and injection speed conditions are selected forachieving a generally homogenous mixture of the feedstock materials. Onesuch protocol might employ a back pressure of about 16 bar, a relativelyslow and gentle screw fill (over about 30 to 35 seconds), and aninjection time of about 2 to about 6 seconds

Following molding or shaping of the articles, they may be subjected toone or more additional secondary operations. For example, they may beflame treated, foamed, bonded, cut, stamped, scored (e.g., by laser,mechanically or otherwise), or otherwise processed.

The teachings herein can be employed to make any of a number ofarticles. Examples include articles selected from one or more of aninstrument panel, a handle, an automotive interior trim panel, aconsole, a component housing, an airbag door, a map pocket, an ash tray,a tonneau cover, a tray, a console, a seat back, an armrest, a kneebolster, a body shield, a front end carrier, a door module, anunder-body shield, an impingement plate, or a cup holder. The articlesherein may further include one or more over molded component, insertmolded component, laminate layer, coating or other component.

The present invention also contemplates kits that include the feedstockconcentrate material, and particularly feedstock concentrate materialpackaged along with the diluent polymeric material.

Though it is possible that handling steps may be employed for achievinga predetermined segregation and/or orientation of reinforcement phase inthe feedstock concentrate material, the finished article preparedtherefrom, or both, one approach herein is to employ a selection ofmaterials, processing steps or both such that a substantially uniformlydispersed reinforcement phase is realized, a randomly orienteddispersion is realized or both.

It should be appreciated from the above, that one or more of thepolymers used herein as the diluent polymer, the first and/or secondpolymer of the feedstock concentrate material, or in the ingredientsconcentrate may be modified for imparting a functional group (e.g.,epoxy modified, carboxylic acid modified acid anhydride modified, or anycombination thereof, for improving bonding. It is generallycontemplated, however, that the embodiments disclosed herein will besubstantially free of a modified polymer in at least the polymers of thefeedstock concentrate material, if not the other polymers as well.

Further, it is possible that fibers employed herein will include one ormore polymeric coatings, such as an inner coating layer of a firstpolyolefin polymer and an outer coating layer of a second polyolefinpolymer. In general, however, the fibers herein prior to contact withthe polymeric phase of the feedstock concentrate material will besubstantially free of any plural layer polyolefin structure. Moreover,it will be appreciated that the fibers will be exposed to the respectivepolymers of the feedstock concentrate material, substantiallysimultaneously during any impregnation step.

The following example illustrates, without limitation, one embodiment inaccordance with the teachings herein.

EXAMPLES

A first concentrate is prepared according to the more preferredcomposition of Table 1. A second concentrate is prepared by impregnating(via pultrusion) a glass fiber bundle with a mixture of the remainingingredients, according to the composition of Table 2. The resultingpultruded concentrate is dry blended with polypropylene impact copolymeravailable commercially from The Dow Chemical Company under thedesignation C705-44NAHP, so that resulting overall glass content isabout 20 percent by weight. The material of the resulting molded articleis expected to realize the following properties of Table 3 within about10 percent of the recited values. An estimated or actual melt flow rateof less than about 100 g/10 minutes is realized (e.g., about 50 to about80 g/10 minutes). Results within about at least about 30, 50 or evenabout 100 percent of the recited values are also believed possible foroverall resulting concentrations of glass at about 30 percent by weightor about 40 percent by weight. For example, at a 30 percent glassconcentration, according to the present teachings, the tensile and/orflexural modulus (as described in Table 3) may be about 7000 MPa, andabout 9000 MPa for about a 40 percent glass concentration. It will alsobe appreciated that the below properties may be reduced by 50 percent,100 percent, or more for resulting materials in instance of relativelylow glass concentration levels (e.g., at about 10 percent by weight oreven about 5 percent by weight). Further, the values specified in Table3 are not limited to the material of the example only. Similar valuesare believed possible for other materials resulting from the teachingsherein.

TABLE 3 ISO Test Property Unit Method value Density Kg/m³ 1183  1030Falling Dart 3 mm @Room Total Energy 6603-2 8.2 Temperature (J) Charpyedge unnotched @Room kJ/m² 179/1eU 44.8 Temperature Charpy flatwiseunnotched @Room kJ/m² 179/1fU 36.3 Temperature Tensile strength at yield50 mm/min MPa 527-2 80.3 Tensile elongation at rupture % 527-2 2.2 50mm/mm Tensile modulus MPa 527-2 4905 Flexural strength MPa 178 125Flexural modulus MPa 178 4712

The explanations and illustrations presented herein are intended toacquaint others skilled in the art with the invention, its principles,and its practical application. Those skilled in the art may adapt andapply the invention in its numerous forms, as may be best suited to therequirements of a particular use. Accordingly, the specific embodimentsof the present invention as set forth are not intended as beingexhaustive or limiting of the invention. The scope of the inventionshould, therefore, be determined not with reference to the abovedescription, but should instead be determined with reference to theappended claims, along with the full scope of equivalents to which suchclaims are entitled. The disclosures of all articles and references,including patent applications and publications, are incorporated byreference for all purposes. Other combinations are also possible as willbe gleaned from the following claims, which are also hereby incorporatedby reference into this written description.

1. A feedstock concentrate material, comprising: a first phase includingfibers having an average length greater than about 5 mm; and a polymericphase including at least 50 percent by weight of the polymericcomponents of the polymeric phase of a first polyolefin having a firstmelt flow rate; and less than 50 percent by weight of the polymericcomponents of the polymeric phase of a second polyolefin having a secondmelt flow rate that is higher than the first melt flow rate; wherein thefibers in the first phase include glass fibers, the first polyolefinincludes a polypropylene and the second polyolefin includes apolypropylene; wherein the feedstock concentrate material furthercomprises a polypropylene-based coupling agent, and the feedstockconcentrate material is in the form of pellets, rods, or granules;wherein the fibers in the first phase are aligned generally axially witheach other; wherein the first polyolefin is a polypropylene having amelt flow rate of less than about 60 g/10 mm, as measured per ISO 1133at 230° C./2.16 kg, the second polyolefin is a polypropylene having amelt flow rate greater than about 300 g/10 mm, as measured per ISO 1133at 230° C./2.16 kg, and the first polyolefin is present from about 3 toabout 9 parts by weight per 1 part by weight of the second polyolefin.2. The feedstock concentrate material of claim 1, wherein the fibers arecoated with a silane sizing, are substantially uniformly distributed inthe blend, or both.
 3. A feedstock concentrate material, comprising: afirst phase including about 50 to about 70 percent by weight of thefeedstock concentrate material of glass fibers coated with a silanesizing and having an average length greater than about 10 mm; apolymeric phase including a blend of: a first polypropylene having amelt flow rate at 230° C./2.16 kg, per Iso 1133 of less than about 60g/10 mm; and a second polypropylene having a melt flow rate at 230°C./2.16 kg, per ISO 1133 greater than about 300 g/10 mm; and a maleicanhydride grafted polypropylene coupling agent present in an amount ofabout 0.5 to about 5 percent by weight of the feedstock concentratematerial; wherein the polymeric phase includes about 3 to about 9 partsby weight of the first polypropylene to about 1 part by weight of thesecond polypropylene.
 4. A feedstock concentrate material of claim 3,wherein the feedstock concentrate material is in the form of pellets,rods, or granules.
 5. A polymeric article comprising a diluent polymerother than the first polypropylene, the second polypropylene or bothblended with the feedstock concentrate material of claim
 3. 6. Thepolymeric article of claim 5, wherein the diluent polymer includes apolypropylene having a melt rate of less than about 150 g/10 minutes, asmeasured per ISO 1133 at 230° C./2.16 kg.